Truck mounted hoist



Aug- 27, 1957 N. J. FARNAM 2,804,216

TRUCK MOUNTED HOIST Filed June 22, 1954 2 shets-sheet 1 50 l 30 tf 54 F lg. Il; "2 I'.

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MM5/m Aug 27, 1957 N. J. FARNAM 2,804,216

TRUCK MOUNTED HOIST Filed June 22, A1954 2 Sheets-Sheet 2 f F/g.2

Newman u. Famam IN V EN TOR.

United States Patent TRUCK MUUNTED HOIST Norman J. Farnam, Enumclaw, Wash.

Application June 22, 1954, Serial No. 438,442 1 Claim. (ci. 212-53) This invention relates generally to hoist mechanisms and has for its primary object the provision of a truck mounted hoist particularly useful for loading objects, such as logs, onto the beds of trucks.

Another object of this invention is to provide an improved truck mounted hoist and novel mounting means therefor which is readily adaptable for use on truck bodies and which includes a novel boom and mast construction incorporating a free swinging boom member and a mast selectively positionable infany one of several positions to eEect the desired loading characteristics, together with sluing means for the boom.

These together with other objects and advantages which will become subsequently apparent reside in lthe details of construction and operation as more fully hereinafter described and claimed, reference being had to the accompanying drawings forming a part hereof, wherein like numerals refer to like parts throughout, and in which:

Figure 1 is side elevational view of a truck equipped with the improved hoist mechanism;

Figure 2 is a plan view of the hoist assembly;

Figure 3 is a vertical irregular section taken substantially along the plane of section line 3 3 in Figure l;

Figure 4 is a horizontal section taken substantially along the plane of section line 4 4 in Figure l;

Figure 5 is a vertical section taken substantially along the plane of section line 5 5 in Figure l;

Figure 6 is a vertical section taken substantially along the plane of section line 6 6 in Figure 4;

Figure 7 is a fragmentary vertical section taken through the mast assembly; and

Figure 8 is a horizontal section through the mast assembly slightly above its flanges showing a modified form of construction.

Referring now more particularly to the drawings, reference numeral 10 indicates an automotive truck which is provided with a conventional bed assembly 12, the truck having the usual longitudinal frame members k14 and 16. At the forward end of the bed 12 is mounted a standard or base 18 of generally A-shaped configuration which includes the downwardly divergent legs 20 and 22 rigidly secured at their lower ends to the frame rails 14 and 16, respectively. Adjacent the upper end of the legs 20 and 22 is a cylindrical 24 which is provided at its upper free end with an annular flange member 26 rigidly secured thereto, as by welding or the like, and, as will be seen most clearly in Figure 7, member 24 is adapted to receive the lower end portion 28 of a mast 30, the mast being provided at an intermediate point with an annular ange or collar member 32 which rests upon the upper surface of the aforementioned flange 26 for rotatably mounting the mast within the cylindrical member 24. The ange 32 is provided with a plurality of circumferentially spaced openings through which a lock pin 34 is selectively received and the flange 26 is provided with a single opening in the position shown clearly in Figure 7 also receiving this pin, and it is to be noted that in this manner, the mast 30 may be rotatably positioned with respect to the cylinder 24 in any one of the several positions corresponding to the various openings in the ange 32.

The ange 32 is provided with a pair of spaced bracket ears 36 between whichv are rigidly secured the bearing members 38 disposed in vertically spaced relation for reception therebetween of an arm portion 40 of the sheave support assembly 42. A vertical pivot pin 44 rotatably connects the sheave support assembly 42 to the bracket ears 36. A boom 46 is pivotally connected to the sheave support 42 by a horizontal pivot pin 48 and the free end of this boom carries a sheave 5i) in the manner shown.

The upper end of the mast 30 is provided with a pair of spaced radial arm members 52 between which a sheave 54 is journaled, as by the pin 56, and to the free end of these bracket arms is connected a chain 58 which includes a detachable link 60 for shortening or lengthening the chain and a cable 62 connected to the free end of the chain is anchored to the sheave 50 at the end of the boom. Since chain 58 is of atxed length, when boom 46 is swung laterally the chain 58 causes boom 46 to rise slightly and this provides a sluing force tending to restore the boom to its normal position over the truck body.

Asseen most clearly in Figures 4-6, a pair of support straps 64 are secured transversely between the frame members 14 and 16 and midway thereon are mounted the bearing members 66 and 68 within which the longitudinally extending shaft 70 is journaled. Rigidly secured to the shaft 7l) directly beneath the cylindrical mast 24 is a drum 72 upon which one end of a cable 74 is wound.` One flange 76 of the drum is provided with a conical recess 78 dening a female clutch member adapted to cooperate with the male clutch element 80 which is rigid with the shaft 70. The element 80 has a sprocket 82 over which a chain 84 is trained which, by engagement over a sprocket on the lay shaft 86 imparts drive force tothe clutch element 80. In this respect, the lay shaft 86 is suitably connected to a power take-off transmission 89 of the vehicle.

The forward end of the male clutch element 80 provides a thrust surface against which the cam element 88 is engaged. The cam element 88 is connected by means of a link 90 vto arhand control lever 92 such thatr upon outward movement of the lever 92, the element 88 will bear against the thrust end of the element 80 and urge this element into engagement with the female clutch element defined by the recess 78, in opposition to the spring 94 normally maintaining these elements out of engagement to effect a drive to the drum 72. The drum ange 76 also provides a brake surface on its outer face and a brake strap 96 dead-ended at one end t-o the vehicle frame extends around this flange for connection to a point on the brake control lever member 98 mounted on the vehicle through a horizontal pivot pin 100 such that upon manipulation of the lever 98, the brake strap will tighten and hold the drum in a desired position.

The cable 74' issues from the drum 72 and passes upwardly therefrom through the cylindrical member 24 and the mast 30 and over the sheave 54 previously described, and thence downwardly over the sheave assembly 42 and outwardly therefrom to the free end of the boom over the sheave assembly 50 and is provided at its free end with a grapple such as the log tongs 102. In operation, the mast 30 is secured in a selected rotatable position with respect to the cylindrical member 24 by insertion of the locking pin 34 in a desired one of its openings and the boomy 46 is manually swung, for eX- ample, pulling on the free end of the cable 74, such that the boom swings to one side of the truck or the other for picking up a load, such as a log. The drum clutch is engaged to lift the load, andthe weight of the load will tend to swing the boom 46 toa position coincidental in direction with the direction in which the bracket arms 52 extend due to the fact that the chain 58 is connected to the free end of the bracket arms `52 at a point radially outwardly from the mast30 with'respect to the position which the vertical pivotpin 44 occupies. This `will effect a sluing moment arm about the pivot pin andswing the boom 46 to the aforementioned coincidental position with the bracket arms 52. 'Thus,'if it is desired'to load a log directly on lthe truck-'bed 12,'the bracketarms 52 are positioned as shown in'Figure'l, and the boom v46 will automatically displace totheA position shown in this figure whenthe log has cleared the side ofthe truck-bed.

As an aid to manipulating the `hoorn when the truck may be disposed on unevensurfaeesor whenever 'the truck is disposed out of level, it may be desired to provide hydraulic cylinder members `104 for controlling the movement of the flange 32 and `consequently the rotatable position of the mast 30. 'In this respect,'it will be VSeen that one end of eachof the 'cylinders 104 isconnected to the opposite ends of a cross-brace member-106 rigid with the A-frarne assembly `18 with-the free end'of the piston rod 108 connected to the ange 32. The cylinders may, of course, be controlled by any suitable Valve mechanism for effecting the rotatable'positioning Of the mast 30. In other respectsthe construction of the modication in Figure 8 is the same as thepreviously described form of the invention. i

It will be readily appreciated that the A-frame assembly not only provides a very rigid mountingfor the hoist, but also permits `the drum assembly '72 to Vbe advantageously positioned directly ybeneath the cylindrical member 24` such that the `cable 74 passes upwardlytherethrough and through the mast 30. This `is an'added safety feature in the event that the cable `74 snaps, since there is less chance for 4whipping of the cable in theevent ofsuch snapping. The bracket arms 52 may be`positioned in any one of a plurality of rotatable positions with respect tothe'cylindrical-member`24 such that a load may be placed at will.' For example, when ,it Vis desired to unload the truckbed `and place the objects to one side of thetruck, the bracket arms 52 will be po sitioned transversely to one side of theitruck or the other which will effectpositioning of the boom 46 in a corresponding manner when the load is freely supported by the boom.

From the foregoing, the vconstruction and operation of the device will be readily understood and further ex- CII planation is believed to be unnecessary. However, since numerous modifications and changes will readily occur to those skilled in the art, it is not desired to limit the invention to the exact construction shown and described, and accordingly, all suitable modifications and equivalents may be resorted to, falling within the scope of the appended claim.

What is claimed as new is as follows:

In combination, a load receiving bed, a hoist support rising from and secured to said bed and including an upper -cylinder provided with a circumferential flange, a hollow mast having a cylindrical lower Vend portion rotatably disposed `in said cylinder and an upper portion rising out of said cylinder, a circumferential flange xed to said mast and forming the separation be- 'tween said portions, said circumferential flange being rotatable on said rst named flange, a vertical pivot pin on the second named flange, a sheave support pivoted on said 'pin for lateral swinging and provided with a first sheave Ioutwardly of said pin, a boom secured to said sheave supportfor lateral swinging, a radial arm on said mast above said sheave support, a second sheave on said'mastabove said first sheave, a kthird `sheaveon the outer end of said boom, a load lifting cable,rdrum means for winding up said cable to lift a load,said cable yextending upwardly through said hollowmast and over the second vsheave,=thence downwardly under ,the first sheave and from'thefrstlsheave -over the third sheave and a'exible elongated-sling-`means 4secured to `said radial arm and the outer end ofsaidboomso that under load on said cable said Asluing means cooperates with said cable and willtend'tofswing said boom laterally about-said pin into vertical lalignment with said arm.

References Cited in theleof this patent 

